Final answer:
To find the probability, divide the number of trees that have both conditions by the total number of trees. Since the number of trees that satisfy both conditions is not given, the exact probability cannot be calculated. However, we can say that the probability is less than or equal to 0.85.
Step-by-step explanation:
To find the probability that a randomly selected tree has both a disease and is being damaged by insects, we need to determine the number of trees with both conditions and divide it by the total number of trees.
Given that 34 trees have a disease or are being damaged by insects, we know that at least 34 trees satisfy one of the conditions. But since we want to find trees that satisfy both conditions, the number of trees that satisfy both conditions will be less than or equal to 34.
Since we don't have the exact number of trees that satisfy both conditions, we can't calculate the exact probability. However, we can say that the probability is less than or equal to 34/40, which is 0.85.
Therefore, the correct answer is none of the given options. The probability that a randomly selected tree has both a disease and is being damaged by insects is less than or equal to 0.85.