3 subshells and 9 orbitals
First of all a subshells and an orbital are completely different.So the 'or' should not be there.
Subshells in a shell is represented by the azimuthal quantum number or secondary quantum number(l).Its value can be between 0 and n-1 where n is the principle quantum number or shell number.l=0 represents the s subshell,l=1 represents the p subshell,l=2 represents d subshell , l=3 represents the f subshell, and so on.
Each subshell has a fixed number of orbitals represented by the magnetic quantum number(m).The s subshell has 1,p has 3, d has 5 , f has 7 and so on.
Thus for M shell, n=3 which means l=0,1,2.Thus it has 3 subshells namely s,p and d.
No of orbitals=s+p+d=1+3+5=9