Rule: Adjective + Preposition Collocation ('prone to'). The adjective 'prone' is followed by 'to' and a verb in the '-ing' form or a noun. The phrase 'prone to something/doing something' means likely to suffer from, do, or experience something regrettable or unwelcome. This fits the context of making sarcastic comments. Option (b) 'prostrate' means lying stretched out on the ground with one's face downward. Options (c) 'prior' and (d) 'immune' do not fit the grammatical structure or meaning.

Rule: Vocabulary - Nouns. The context of 'making way for a new' building implies the old one was torn down. 'Demolition' is the action or process of demolishing or knocking down a building. Option (b) 'construction' is the opposite. Option (c) 'renovation' means to restore or repair. Option (d) 'consecration' means to make something sacred. 'Demolition' is the only logical choice.

Rule: Subjunctive Mood for Past Regrets. The verb 'wish' is used to express regret about a past situation. The structure for this is 'Subject + wish + subject + past perfect tense (had + V3)'. The speaker is regretting a lack of knowledge in the past. Therefore, the past perfect 'had known' is the correct form. Option (b) 'knew' is used for wishes about the present (e.g., 'I wish I knew the answer now'). Options (a) and (c) are grammatically incorrect in this structure.

Rule: Vocabulary - Adjective Choice. The result of the arguments was that 'we all agreed'. This implies the arguments were convincing. 'Persuasive' means good at persuading someone to do or believe something through reasoning or the use of temptation. This fits the context perfectly. Options (a) 'precarious' and (b) 'perilous' both mean dangerous or risky. Option (d) 'pessimistic' means tending to see the worst aspect of things.

Rule: Phrasal Verbs with 'Hand'. The context is about submitting work. The phrasal verb 'hand in' means to submit something (especially an assignment) to a person in authority. Option (b) 'hand out' means to distribute. Option (c) 'hand over' means to give control of something to someone else. Option (d) 'hand down' means to pass on knowledge or to give a formal judgment. 'Hand in' is the only correct choice for submitting an essay.

Rule: Adjective + Preposition Collocation. The adjective 'susceptible' is always followed by the preposition 'to'. The phrase 'susceptible to something' means likely or liable to be influenced or harmed by a particular thing. This is a fixed grammatical pairing. Options (a) 'for', (b) 'of', and (c) 'with' are incorrect prepositions to use with 'susceptible'.

Rule: Vocabulary in a Legal Context. The phrase 'lack of evidence' suggests the defendant will be cleared of blame. 'Absolve' means to declare someone free from guilt, obligation, or punishment, which is the appropriate legal term. Option (a) 'accuse' and (b) 'convict' are antonyms of the required meaning. Option (d) 'activate' is irrelevant to the context.

Rule: Subject-Verb Agreement with 'A number of'. The phrase 'A number of' is followed by a plural noun ('applicants') and takes a plural verb. It is treated as a plural subject. In contrast, 'The number of' takes a singular verb. Therefore, the plural verb 'have' is correct. Options (a) 'has', (c) 'is', and (d) 'was' are all singular verbs.

Rule: Vocabulary - Choosing the Correct Adjective. The effect described (students falling asleep) indicates that the lecture was long, slow, or dull. 'Tedious' means too long, slow, or dull: tiresome or monotonous. This fits the context perfectly. Option (b) 'terrific' means excellent. Option (c) 'tactful' means having skill and sensitivity in dealing with others. Option (d) 'tenable' means able to be defended against attack or objection.

Rule: Conditional Conjunctions. This sentence presents a negative condition. 'Unless' means 'except if' and is used to introduce the only situation in which an event will not happen. 'Unless you work harder' means 'If you do not work harder'. Option (b) 'If' would require a negative verb in the clause ('If you do not work harder...'). Option (c) 'Although' introduces a contrast, which doesn't fit the logic. Option (d) 'Until' refers to time, not a condition.