(a) A and B are correct.The coefficient of linear expansion,α=L1​ΔTΔL​=[LT][L]​=K−1 Here, L= initial length△L= change in length△T= change in temperatureOn the other hand, the coefficient of volume expansion,γ=V1​ΔTΔV​=[L3T][L3]​=K−1 Here, V= initial volume△V= change in volume△T= change in temperature△T= change in temperature K= kelvin, the S.I. unit of temperature