Correct Answer - n =22.
Here, a= 12, d= 4, `t_(n ) = 96, n = ?`
`t_(n) = a + ( n -1) d ` …(Formula)
`:. 96 = 12 + ( n-1) xx 4 ` …(Substituting the values)
` :. 96 -12 = ( n-1) xx 4 `
`:. 84 = ( n-1) xx 4 `
`:. ( 84)?( 4) n-1` `:. 21 = n -1`
`:. n = 21 + 1 ` `:. n = 22`