Both options (verb in singular or plural) are correct. However, there are certain situations where it is better to use singular. Have a look at these examples:

• Большинство сказало правду

Here, there is no noun after “большинство”, so the verb is in agreement with “большинство” which is neuter and singular.

• Большинство населения сказало правду

Here, the noun after “большинство” is in genitive singular, so the verb should also be singular.

Here we see situations where it is better to use plural:

• Большинство домов были старыми

Here we find an adjective after Большинство. The adjective must be plural because it refers to “домов”, so the verb should be also plural.

• Большинство людей, которые работали на заводе, сказали правду

If the noun in genitive plural that goes after “большинство” and the verb are separated by many words, it’s better to put the verb in plural.

We have to do it this way, to make the sentence easy to understand. And now, have a look at this simple sentence where we can use both singular and plural:

• Большинство людей сказало правду

In this case, we consider those people as a group.

• Большинство людей сказали правду

In this case, we consider those people separately, they don’t form a group.