Which of the following sentences has correct subject-verb agreement?

a.

Lady Macbeth, mistress of many servants, walk to the banquet hall.

b.

When approaching the palace, Banquo, not Fleance, are killed.

c.

Fleance, without Banquo, escape.

d.

When he first enters the banquet hall, Macbeth appears cheerful.

The correct answer is D. When he first enters the banquet hall, Macbeth appears cheerful.

Subject-verb agreement means that the subject and the verb must agree in number - if the subject is singular, the verb has to be singular as well; if the subject is plural, the verb should also be plural.

A is incorrect because it should be 'walks,' B is incorrect because it should be 'is,' and C is incorrect because it should be 'escapes.'