An object has a positive charge whenever

it has a deficiency of electrons
it has an excess of electrons
the nuclei of its atoms are positively charged
the electrons of its atoms are positively charged

it has a deficiency of electrons

Explanation:

As we know that charge of a given matter is

here N = number of electrons

e = charge of an electron

here we always say that charge of a given system is due to transfer of electrons as they are loosely bounded with the nucleus of an atom

So here since we know that electrons are negatively charged and when an atom loses electron then it will have net positive charge on it.

So when an object is having positive charge on it then it means it must lose some electrons so it will remain positive charge on it

1 a

2 b

3 b

4 d

5 d

6 d

explanation:

see earlier answer