A hollow-cathode lamp is（）

A hollow-cathode lamp is( )

A．a narrow-band light source B．a broad-band light source

C．a light detector D．not a light source

A. A broad-band light source

B. A narrow-band light source

C. A light detector

D. Not a light source

A.Pinus massoniana Lam

B.PINUS MASSONIANA LAM

C.pinus massoniana lam

D.Pinus Massoniana Lam

E.

A.rum

B.lam

C.raw

_________________(别让火灭了) when lam out.