Directions: There is some relationship between the two pair of letters on the left of the sign (::). The same relationship exists between the two terms on the right of which one is missing. Find the missing one from the given alternatives.

HJLN : ? : : IKMO : RTVX

The pattern involves alternating jumps: +2, +1, +2, +1. For HJLN: H(8)+2=J(10), J(10)+1=K, K+2=L, L+1=N. For IKMO: I(9)+2=K(11), K(11)+1=M, M+2=O, O+1 gives? This doesn't perfectly match. Looking at IKMO:RTVX, the right side also follows +2,+1 pattern. For HJLN, applying this: H(8)+2=J(10), then Q(17), S(19), U(21), W(23) doesn't fit the pattern perfectly. Actually, the correct pattern is that each letter is followed by a letter 2 positions ahead, then 1 position ahead, alternating. So H(8)->J(10) [+2], then we need a letter that fits the second sequence. Let me reconsider: HJLN and IKMO are both 4-letter sequences. RTVX is the result for IKMO. For HJLN: H(8), J(10), L(12), N(14). If we apply the same +2 pattern consistently: H+2=J, J+2=L, L+2=N. Then the next would be N+2=P, P+2=R, R+2=T, but this gives PNRT. The actual answer is QSUW. Let me re-examine: Q(17)=H+9, S(19)=J+9, U(21)=L+9, W(23)=N+9. So the pattern is +9 to each corresponding position.