A. Grass is not eaten by a lion, however hungry he may be
Feedback Simple present ‘does not eat’ needs to become ‘not eaten’ for the conversion into passive form. So, option (b) and option (d) are rejected as they use ‘being’ which is generally used with present or past continuous forms. Out of option (a) and option (c), the latter is rejected as it does not conform to proper sentence formation rules
B. Grass is not being eaten by a lion, however hungry he may be
C. Grass is eaten not by a lion, however hungry he may be
D. Grass is being not eaten by a lion, however hungry he may be