Question 43317
{{{a[1] = -4}}}
{{{a[2] = -4}}}


Now,
{{{a[n+2] = a[n+1] - 4a[n]}}}


When, n = 1,
{{{a[1+2] = a[1+1]-4a[1]}}}
or {{{a[3] = a[2]-4a[1]}}}
or {{{a[3] = -4 -4*(-4) = 12}}}


When, n = 2,
{{{a[2+2] = a[2+1]-4a[2]}}}
or {{{a[4] = a[3]-4a[2]}}}
or {{{a[4] = 12 -4*(-4) = 28}}}


When, n = 3,
{{{a[3+2] = a[3+1]-4a[3]}}}
or {{{a[5] = a[4]-4a[3]}}}
or {{{a[5] = 28 - 4*12 = -20}}}


Hence, (c) is correct.