What is the confidence of the rule (hat, scarf) -> gloves?

Consider these itemsets:
(hat, scarf, coat)

(hat, scarf, coat, gloves)
(hat, scarf, gloves)
(hat, gloves)
(scarf, coat, gloves)
What is the confidence of the rule (hat, scarf) -> gloves?

A.
66%

B.
40%

C.
50%

D.
60%