Most favourable conditions in which I am top posssibly (6)
I believe the answer is:
optima
'most favourable conditions' is the definition.
(I've seen this before)
'which i am top posssibly' is the wordplay.
'i am top' can be anagrammed to 'OPTIMA'.
However, I'm unsure how the anagram is indicated.
'in' is the link.
Can you help me to learn more?
(Other definitions for optima that I've seen before include "Points at which conditions are most favourable" , "Ideal conditions" , "Conditions producing the best possible results" .)