$1.$ Which instruction in the following MIMPS sequence may cause a data hazard?

$$ add $t$0,$ $s$1,$ $s$2$

$$ sub $t$1,$ $t$0,$ $s$3$

$$ lw $t$2,0($$s$4)$

$$ or $t$3,$ $t$1,$ $t$2$

$$ sw $t$3,0($$s$5)$

A$)$ add $t$0,$ $s$1,$ $s$2$

B$)$ sub $t$1,$ $t$0,$ $s$3$

C$)$ lw $t$2,0($$s$4)$

D$)$ or $t$3,$ $t$1,$ $t$2$