Why not use 'about' instead of 'of'?

[Peter]

English Grammar Tests, Elementary Level

ESL/EFL Test #91 "Using Prepositions", question 10

Karen is very jealous ......... Kim and it's very obvious to others.

(a) of
(b) about
(c) at
(d) with

English Grammar Tests, Elementary Level

ESL/EFL Test #91 "Using Prepositions", answer 10

Karen is very jealous of Kim and it's very obvious to others.

Correct answer: (a) of

Your answer was: incorrect
Karen is very jealous about Kim and it's very obvious to others.
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why not use about instead of of in this sentence? would you like to explain for me?

peter

[Pamela]

The expression is to be jealous of;