Correct Answer: C

Rationale: In this sentence, the correct choices are 'They're' and 'their.' 'They're' is a contraction of 'they are,' which fits the context of the sentence as it suggests ownership of the dog. 'Their' is a possessive pronoun showing ownership. Choice A is incorrect as 'there' refers to a place and doesn't make sense in this context. Choice B is incorrect as the possessive pronoun 'their' should come before the noun 'dog'. Choice D is incorrect as 'they're' should be used before the verb 'having trouble' to form a contraction for 'they are'.

Correct Answer: C

Rationale: The correct answer is 'C: Preventive measure.' A precaution is a preventive action taken to avoid harm or danger. 'Rule' (A) and 'Habit' (D) do not capture the essence of being cautious to prevent something negative. 'Routine procedure' (B) is related to a regular way of doing things, but it does not specifically imply taking action to prevent harm.

Correct Answer: A

Rationale: The correct answer is A, 'Complex.' The term 'convoluted' is used to describe something that is intricate, complex, or twisted. 'Clever' (choice B) means showing intelligence or skill, 'Candid' (choice C) means truthful and straightforward, and 'Asinine' (choice D) means extremely foolish or silly. These choices do not accurately reflect the meaning of 'convoluted.'

Correct Answer: C

Rationale: The correct answer is C because the environment refers to the surroundings or conditions in which a person, animal, or plant lives or operates, encompassing both internal and external factors. Choices A, B, and D are incorrect as they do not accurately define the concept of 'environment.' Choice A is too broad and does not specifically address the components of an environment. Choice B is vague and does not capture the entirety of what an environment entails. Choice D is limited in scope, focusing solely on a home environment rather than the broader concept of environment.

Correct Answer: C

Rationale: The correct answer is C: 'Easiest.' The word 'easiest' is the correct superlative form of 'easy,' which is used to compare one item against others in terms of degree. 'Most easiest' and 'most easy' are grammatically incorrect. Choice D, 'Easy,' is incorrect as it is not a superlative form and does not convey a comparison of the test against others in the course.