Final answer:
Without the thermal conductivity of human tissue, the precise calculation of heat transfer rate by conduction cannot be performed. Comparing this to heat generated from an energy intake is complex, but generally, metabolism should contribute to a higher heat transfer rate than conduction alone.
Step-by-step explanation:
The rate of heat transfer by conduction through the human body's tissue can be calculated using Fourier's law of heat conduction. However, to determine this rate accurately, one would also need the thermal conductivity of the tissue, which is not provided. Without this value, a precise calculation cannot be performed. Even if we had the conductivity value, comparing this rate to the heat generated from an energy intake of 2400 kcal per day is complex because the body's metabolism involves many forms of heat transfer, not just conduction.
On average, the human body, with a metabolic rate accounting for 2400 kcal/day, will have a much higher heat transfer rate through metabolism than through conduction alone, as energy intake leads to heat generation within the entire body, while conduction primarily occurs across the skin layer where there is a temperature difference.
In conclusion, without specific conductivity values or additional details on the exact contexts of both scenarios, a direct comparison is not feasible. However, it is generally expected that option c) Higher through energy intake is correct, as metabolic processes are typically the primary source of heat in the body.