Let’s count the stations traversed on each route.
M3 → M2: 1 station.
M2 → B8: Note that M2 = B10, so this is actually B10 → B8. 2 stations.
B8 → C3: Note that B8 = R3 and C3 = R5, so this is actually R3 → R5. 2 stations.
C3 → O3: Note that O3 = C2, so this is actually C3 → C2. 1 station.
A total of 1+2+2+1 = 6 stations.
M3 → C4: Note that C4 = M5, so this is actually M3 → M5. 2 stations.
C4 → O4: Note that O4 = M6, so this is actually M5 → M6. 1 station.
O4 → O3: 1 station.
A total of 2+1+1 = 4 stations.
M3 → M5: 2 stations.
M5 → O3: Notice that M5 = C4 and O3 = C2, so this is actually C4 → C2. 2 station.
A total of 2+2 = 4 stations.
M3 → B10: Note that B10 = M2, so this is actually M3 → M2. 1 station.
B10 → B5: 5 stations.
B5 → O3: Note that B5 = C1 and O3 = C2, so this is actually C1 → C2. 1 station.
A total of 1+5+1 = 7 stations.