Your sister might even stay in school, if you lead by example.

Which of these would make the sentence conditional in mood?

A.

example

B.

might

C.

stay

D.

lead

The answer is B. might.

Explanation:

First, let's identify which conditional this is, so we'll have to name the verb parts of these clauses:

If you lead by example - verb is lead and it is present simple tense.

your sister might even stay in school - might stay - it a modal construction that consists of a modal verb might and bare infinitive of a verb to stay

This combination is seen in the second conditional. Modals can be: would, might, can, may ...

Answer A - example does not affect the sentence in any way.

Answers C and D - stay and lead - those are the verbs that have to be in these clauses. So what is needed so that this can be a conditional sentence is modal verb might.