(A) Principle quantum number n is a positive integer and it's possible values are n = 1, 2, 3 ........

$$\therefore$$ A is correct.

(B) Azimuthal quantum number 'l' for a given 'n' can have values as l = 0, 1, 2 ....... (n $$-$$ 1)

$$\therefore$$ Statement B is wrong.

(C) Magnetic orbital quantum number m_l for particular l has values from $$-$$ l to + 1 including zero means 2l + 1 values.

$$\therefore$$ Statement C is correct.

(D) $$ \pm \,\,{1 \over 2}$$ are the two possible orientation of electron spin.

$$\therefore$$ Statement D is correct.

(E) For l = 5, there will be a total of 11 orbitals.

$$l$$ = 0 $$\Rightarrow$$ 5 subshell

$$l$$ = 1 $$\Rightarrow$$ p subshell

$$l$$ = 2 $$\Rightarrow$$ d subshell

$$l$$ = 3 $$\Rightarrow$$ f subshell

$$l$$ = 4 $$\Rightarrow$$ g subshell

$$l$$ = 5 $$\Rightarrow$$ h subshell

We know,

Number of orbital in any subshell = 2$$l$$ + 1.

$$\therefore$$ For h subshell, number of orbitals = 2 $$\times$$ 5 + 1 = 11