Number of bones in hind-limb of human is (A). 21(B). 24(C). 30(D). 14

To answer the question, let's first examine the human hind limb's bone structure:

Pelvic girdle: The pelvic girdle consists of two hip bones (each called the os coxae), making a total of 2 bones.
Thigh (Femur): The femur is the long bone of the thigh, and there is one femur in each leg, so 2 femurs.
Knee (Patella): There is one patella (knee cap) in each leg, so 2 patellae in total.
Leg (Tibia and Fibula): The tibia and fibula are the two bones in the lower leg, and there are 2 tibiae and 2 fibulae in total, so 4 bones.
Ankle and Foot (Tarsals, Metatarsals, and Phalanges):
There are 7 tarsal bones in each foot (14 tarsals in total for both feet).
There are 5 metatarsals in each foot (10 metatarsals in total).
The number of phalanges (toes) is 14 in total (2 in the big toe and 3 in each of the other toes, for each foot).
Now, let's add up the bones in the hind limb:

2 pelvic girdle bones
2 femurs
2 patellae
4 tibiae and fibulae
14 tarsals
10 metatarsals
14 phalanges
Total = 2 + 2 + 2 + 4 + 14 + 10 + 14 = 48 bones.

However, the question asks for the number of bones in the hind limb only, which generally excludes the pelvic girdle from this count. If we exclude the pelvic girdle, we have:

2 femurs
2 patellae
4 tibiae and fibulae
14 tarsals
10 metatarsals
14 phalanges
This adds up to 2 + 2 + 4 + 14 + 10 + 14 = 46 bones in total in the hind limb.

Since the options are:

(A). 21
(B). 24
(C). 30
(D). 14

The correct answer is None of these options. Based on the above reasoning, the correct number of bones in the hind limb of a human is 30 or 46, depending on whether you include the pelvic girdle. Since none of the options match this exact number, there seems to be an error in the options provided.