What is the smallest summary route that can be advertised covering these four subnets?

A router has four interfaces addressed as 10.1.1.1/24, 10.1.2.1/24, 10.1.3.1/24, and 10.1.4.1/24.
What is the smallest summary route that can be advertised covering these four subnets?

A.
10.1.2.0/22

B.
10.1.0.0/22