Meaning of "cold feet"

[golf]

Test No. incompl/inter-18 "Hot and Cold", question 3

Although I'd made up my mind to do it last night now I'm not sure and am getting cold ......... about it.

(a) hands
(b) feet
(c) legs
(d) arms

Test No. incompl/inter-18 "Hot and Cold", answer 3

Although I'd made up my mind to do it last night now I'm not sure and am getting cold feet about it.

Correct answer: (b) feet

Your answer was: incorrect

Although I'd made up my mind to do it last night now I'm not sure and am getting cold arms about it.
________________________

Why have to be "cold feet"?
What does it mean?

Give me some answer please.
Golf

[Torsten]

If you get cold feet about something, you lose the courage to do it.
_________________
Test Of English for International Communication
TOEIC Preparation & TOEIC Vocabulary

[Haihao]

Hi,

[Yankee]

Hai Haihao

Yes, the 'd means had. You can use either the past perfect or the simple past tense here. I wouldn't consider using the past perfect to be colloquial. On the contrary, it sounds more formal than the simple past tense.

Amy

[Haihao]

Hai Amy, Ni-hao! (Chinesisch, = Guten Tag)

Danke shon wieder!

Hai-hao.