On a section with a steep slope where the simultaneous passage of two vehicles travelling in opposite directions is very difficult or impossible, which vehicle will have priority?

On a section with a steep slope where the simultaneous passage of two vehicles travelling in opposite directions is very difficult or impossible, which vehicle will have priority?
A)The vehicle travelling uphill.Correct
B)The vehicle travelling downhill.
C)The one with the greatest difficulty in passing.
On sections with a steep slope, a minimum of 7%, priority will be for the vehicle travelling uphill, unless it could reach a passing place established for that purpose first.