Read this passage:
the trouble is, of course, that they put up that sign saying
what flavors they have, with little cardboard inserts to put
in or take out flavors, way back when they first opened the
store. but they never change the sign- or not often
enough. they always have flavors that aren't on the list,
and often they don't have flavors that are on the list.
children know this - whether innately or from earlier
experience it would be hard to say.
what is the main idea of this passage from "how to eat an ice-cream cone"?
o
a. children have an easier time ordering ice cream cones than adults
do.
b. the ice cream flavor board should be constantly updated.
o
c. deciding on what flavor of ice cream everyone wants is difficult.
o
d. ice cream stores often run out of flavors or add new flavors to
their signs.

B. The ice cream flavor board should be constantly updated.

Explanation:

The main idea of the passage is described in the first line of this paragraph i.e. "The trouble is, of course, that they put up that sign...". This problem/idea is discussed in next few lines. In the last part of this passage, the writer tells the readers about children's special abilities to identify the flavors just by names, without the signs.

Option A is not correct firstly because the writer has clearly stated the main idea by calling it "the trouble"  and secondly the passage is about ice-cream and not about children's abilities.

Option C is incorrect because the passage says nothing deciding on flavor of ice creams.

Option D is incorrect because it is contrary to what is described in the passage. Passage says they don't update signs. Moreover adding new flavors is not result of running out of flavor.

i think that the best option for this question is

d)to persuade readers that a prince must eradicate the royal family of a conquered principality.

i hope this .