If the measure of the vertex angle of an isosceles triangle is an integer, then the measure of each base angle is an integer.
O A) Sometimes; only if the measure of the vertex angle is even.
OB) Sometimes; only if the measure of the vertex angle is odd.
O C) Always; because the measure of the vertex angle is an integer, the measure of each base angle must also be an integer.
OD) Never; because the measure of each base angle is equal to the difference of 180 and the measure of the vertex angle divided by 2, each measure is a rational number.​