Which is the longest bone in the human skeletal system?

The $Humerus$ bone is situated in:

Mark the odd one with respect to girdle bones.

In which bone is the patellar groove found?

$A$: Tibia is stronger and is present medially,whereas fibula is the outer and slender bone of the lower leg or shank.
$R$: Tibia has a sharp crest in the shaft and a projection on the inner side of the ankle called the lateral malleolus.

Bones of pectoral and pelvic girdle help in the articulation of: