Question

cause means :
a race in which competitors must negotiate obstacles
the number of occurrences within a given time period
the property of being scattered about over a range or area
an entity that produces an effect

Explanation:

Let's analyze each option:

• Option 1: A race with obstacles is an "obstacle - race", not related to the meaning of "cause".
• Option 2: The number of occurrences in a time - period is related to "frequency", not "cause".
• Option 3: The property of being scattered is related to "dispersion", not "cause".
• Option 4: According to the dictionary, "cause" can be defined as an entity that produces an effect.

Answer:

an entity that produces an effect