Concentration of H+ ions in HNO3 solution is 10⁻¹ which is equal to 0.1 M
[tex] \bf \: pH \: = - log[{h}^{ + }][/tex]
putting the value we get
[tex] \sf \dashrightarrow \: pH \: = - log \: [ \frac{1}{10}] \\ \\ \sf \dashrightarrow \: pH \: = - log \: {10}^{ - 1} \\ \\ \sf \dashrightarrow \: pH \: = 1[/tex]
So, the required option is A) 1
