Cathode rays

Which of the following is correct?
Antara yang berikut, yang manakah betul?

A Electrons are emitted from the anode.
    Elektron dipancarkan dari anod.

B Cathode rays cannot be reflected by an electric field.
    Sinar katod tidak dapat dipesongkan oleh medan elektrik.

C Protons are emitted from the cathode.
    Proton dipancarkan dari katod.

D Electrons are emitted from the cathode.
    Elektron dipancarkan dari katod. 



Answer : D
When the filament is heated, electrons are emitted frm the cathode.