( a ) are present on the inside wall of seminiferous tubules multiply by meiotic division and remain constant in numbers
( b ) are present on the inside wall of seminiferous tubules multiply by mitotic division and remain constant in numbers
( c ) are present on the inside wall of seminiferous tubules multiply by meiotic division and increase in numbers
( d ) are present on the inside wall of seminiferous tubules multiply by mitotic division and increase in numbers
