This question tests your ability to decipher a code based on given examples. Let's analyze the provided code:

• BEAUTY is coded as 71
• RIVER is coded as 70

Observe that the code doesn't seem to be based on alphabetical order or simple numerical substitution. Instead, let's consider the numerical values of the alphabets. Assign numerical value to each alphabet from A=1 to Z=26. Now sum the values of the alphabets in each word.

• BEAUTY: B(2)+E(5)+A(1)+U(21)+T(20)+Y(25) = 74
• RIVER: R(18)+I(9)+V(22)+E(5)+R(18) = 72

It appears there's a pattern of subtraction. Notice that 74 - 3 = 71 (BEAUTY) and 72 - 2 = 70 (RIVER). It seems the code is obtained by subtracting a number related to the word length from the sum of alphabet values. The number to be subtracted is (word length -1). Let's verify it with the word 'PEOPLE':

• PEOPLE: P(16)+E(5)+O(15)+P(16)+L(12)+E(5) = 70

Length of PEOPLE is 6. Subtracting (6-1)=5 from 70 gives 65. However, it contradicts the pattern observed in BEAUTY and RIVER. Let's re-examine. The pattern seems to be subtracting the position value of the last alphabet. For BEAUTY, Y is at 25th position, so 74 - 25 = 49. Again, for RIVER, R is at 18th position, so 72 - 18 = 54. This pattern is not consistent either. Let's try another approach. It seems the code is obtained by summing the position of each alphabet and subtracting a constant, say X. Let's try this approach:

• BEAUTY (B=2, E=5, A=1, U=21, T=20, Y=25): 2+5+1+21+20+25 = 74. 74 - X = 71 => X = 3
• RIVER (R=18, I=9, V=22, E=5, R=18): 18+9+22+5+18 = 72. 72 - X = 70 => X =2

This approach isn't consistent either. There must be a different underlying pattern that we've not yet identified. Therefore, there's an error in the question's logic or the provided codes for BEAUTY and RIVER.

Considering the provided options and assuming a different logic, the best approximation is 66