Depending on the radiating properties, a body will be opaque when _________________?

Depending on the radiating properties, a body will be opaque when _________________?

A. p = 0, x = 0 and a = 1
B. p=l,x = 0anda = 0
C. p = 0, x = 1 and a = 0
D. x – 0, a + p = 1
E. a=0,x + p= 1.
where a = absorptivity, p = reflectivity, X = transmissivity