The given inequality is
[tex] 90 < -30p + 15 [/tex]
We need to isolate p, and for that , first we subtract 15 to both sides, that is
[tex] 90-15< -30p+15-15 [/tex]
[tex] 75 < -30p [/tex]
Dividing both sides by -30. And on dividing by negative number, the sign of the inequality change . That is
[tex] -2.5>p \\ p<-2.5 [/tex]
And -10 is less then -2.5 . So the correct option is
[tex] p=-10 [/tex]