31) the mass of an electron is approximately 1/1836
times the mass of
a) 1/1h
b) 2/1h
c) 3/1h
d) 4/2he

 is the correct choice that is option A.

Explanation:

An electron has times the mass of a proton, but an equal and opposite negative charge.

Lets is any element represented here.

Where is the number of protons as well as its atomic number.

And

is the mass number which is the number of protons and neutrons in any atom.

Note: We know that Hydrogen is devoid of neutron,so number of neutrons in a Hydrogen atom is zero.

Then

is also a representation of single proton.

So is the right choice that is option A.

i need mutiple choices