Which of the following statements is true?

$1)$ If activity is higher than expected, total variable costs should be higher than expected AND If activity is lower than expected, total fixed costs should be lower than expected.

$2.$ In a flexible budget, when the activity declines, the unit variable cost also declines.

A$)$ Only statement I is true.

B$)$ Only statement II is true.

C$)$ Both statements are true.

D$)$ Neither statement is true.