The correct option is
B Epiphytic roots of orchids
Epiphytic roots are adventitious roots found in the epiphytes. These roots are present in the air and absorb the moisture
and nutrients from the air by a special type of tissue called as velamen. Velamen is an outer epidermis layer of epiphytic roots. Since epiphytic plants
do not have roots in the soil, they are called as air plants. Epiphytic roots of orchids grow on the surface of other plants for getting shelter.
Hence, the correct option is B.