The correct option is C Germinating seed
Growing shoot apex :
Growing shoot apex has meristematic cells which actively divide to increase the length of the shoot apex.
These cells do not show a high rate of respiration.
Germinating seed :
Germinating seed actively divides and grows itself. It requires a high rate of metabolism to obtain energy for its growth. Thus, it shows a high rate of respiration.
Root tip and leaf bud :
Root tip has meristematic cells which actively divide to increase the length of the root. For this purpose, they do not need to break glucose. Hence, they do not show a high rate of respiration.
Leaf bud remains in a dormant state. In this state, they slow down their metabolism. Thus, leaf buds have the slowest rate of respiration.
Final answer : Germinating seed