The direction of synthesis of an RNA transcript is ____ .
A$1^{\prime} \longrightarrow 5^{\prime}$
B5' ⟶ 3'
C1' ⟶ 3'
D3' ⟶ 5'
E$2^{\prime} \longrightarrow 4^{\prime}$
A$1^{\prime} \longrightarrow 5^{\prime}$
B5' ⟶ 3'
C1' ⟶ 3'
D3' ⟶ 5'
E$2^{\prime} \longrightarrow 4^{\prime}$