Kate is a florist. Kate can arrange $20$ bouquets per day. She is considering hiring her husband William to work for her. William can arrange $18$ bouquets per day. What would be the total daily output of Kate's firm if she hired her husband?

a$.$

$19$ bouquets

b$.$

$20$ bouquets

c$.$

$38$ bouquets

d$.$

$18$ bouquets