Find the Unit Tangent Vector T and the Principal Unit

Multiple Choice

Find the unit tangent vector T and the principal unit normal vector N.
-r(t) = ( 7t sin t + 7cos t) i + ( 7t cos t - 7 sin t) j - 4k

A) T = (cos t) i + (sin t) j; N = (-sin t) i + (cos t) j
B) T = (-cos t) i - (sin t) j; N = (sin t) i - (cos t) j
C) T = (cos t) i - (sin t) j; N = (-sin t) i - (cos t) j
D) T = (-cos t) i - (sin t) j; N = (sin t) i + (cos t) j