what does "count on" mean?

[Kothow]

English Language Tests, Intermediate level

ESL/EFL Test #273 "When do you say this?", question 7

I say "You can count on me" when I ..........

(a) trust someone
(b) support someone
(c) dislike someone

English Language Tests, Intermediate level

ESL/EFL Test #273 "When do you say this?", answer 7

I say "You can count on me" when I support someone.

Correct answer: (b) support someone
_________________________

count on? what does it mean?

Kothow

[Mister Micawber]

.
Rely on
.
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Canadian-American native speaker
who teaches English for a living at Mister Micawber's
ESL cafe: Interview with Mister Micawber