Write the expression in quadratic form, if possible. a^8 + 10a^2 - 16, algebra homework help

Writetheexpressioninquadraticform,ifpossible.a^8+ 10a^2- 16A.(a^4)^2+ 10(a^2) - 16B.(a^2)^2+ 10(a^2) - 16C.a^2[(a^2)^2+ 10(a)] - 16D.cannot be written in quadratic form