Query on as 13

hello friends,

i am writing CMA CC I stuck up with one question as follows

A Company held 25% stake in another company and during the year it withdrew the investment to the extent 10%. How should the company account for the investment

(a) treat investment as per AS 13 for the whole year

(b) Account for as per equity method till date of withdrawal of investment and thereafter as per AS 13

(c) Account for as per equity method for the whole year

Which option is correct and how or why?

Pl help me