Answer:
To convert temperature from the new scale (X) to Celsius, we simply subtract 0 from the value in X and then multiply the resulting number by a factor of 100/70. This gives us the Celsius temperature.
For 35° X, we can use the formula as follows:
C = (35 - 0) * (100/70)
C = 35 * 1.4286
C = 50°C
Therefore, the correct answer is option A, which is 50.