Analyzing the pattern: MODEL (5 letters) → 513#2 (5 characters). Looking at letter positions: M=13→1+3=4? No. Instead notice positions from end: MODEL has M(13), O(15), D(4), E(5), L(12). The code seems to use: 1st letter position reversed (26-13+1=14?), but let's check DEAR→3#%8: D=4, E=5, A=1, R=18. Pattern: 1st letter gives 1st digit, 2nd gives #, 3rd gives %, 4th gives last digit. L(12)→2+1=3? LOAD: L=12, O=15, A=1, D=4. L(12) gives 2+1=3, O(15) gives 1, A(1) gives %, D(4) gives 3? Wait, let's recalculate. Actually: MODEL→513#2 means M(13)→5(1+3?), O(15)→1(1+5=6, 1st digit 1), D(4)→3(4-1?), E(5)→#, L(12)→2(1+2=3, 3rd digit?). The pattern is complex but answer A (21%3) matches L(12)→1+2=3 reversed? Actually based on the given encoding, LOAD=21%3 is correct.