'they' is plural and requires the plural verb 'have' instead of 'has.' The pronoun 'they' must agree with a plural verb form.

'Demand' is singular and requires 'has' instead of 'have.' The subject does not agree with the verb in number.

The passage explicitly states that 'ethical concerns regarding data privacy and job displacement remain significant challenges,' making option B the correct answer.

The context suggests that renewable energy sources are becoming more and more viable, making 'increasingly' the most appropriate choice.

The passage presents both positive aspects (flexibility, autonomy) and negative aspects (lack of benefits, income volatility), indicating a balanced view of the gig economy.

'Ameliorate' means to make something better or improve it. In this context, it refers to improving the quality of learning outcomes.

'Altered' indicates significant change in behaviors, which is appropriate given the transformative nature of e-commerce on consumer habits.

The word 'while' introduces a contrasting idea, acknowledging the advantage of remote work while presenting a disadvantage simultaneously.

The passage emphasizes that businesses need to adopt these technologies or risk becoming obsolete, making option B the main idea.

Committee is a collective noun that takes a singular verb in formal English. 'has' is correct, not 'have'.