Read this paragraph from the essay. I have now been in India for over two years and a half after my return from South Africa. Over one quarter of that time I have passed on the Indian trains travelling third class by choice. I have travelled up north as far as Lahore, down south up to Tranquebar, and from Karachi to Calcutta. Having resorted to third class travelling, among other reasons, for the purpose of studying the conditions under which this class of passengers travel, I have naturally made as critical observations as I could. I have fairly covered the majority of railway systems during this period. Now and then I have entered into correspondence with the management of the different railways about the defects that have come under my notice. But I think that the time has come when I should invite the press and the public to join in a crusade against a grievance which has too long remained unredressed, though much of it is capable of redress without great difficulty.

How does the author's decision to use the word crusade to describe a protest movement affect the text?

It makes the protest sound especially strong and committed.

It adds an element of irony to the description of the protest.

It implies that the protesters will not back down, no matter what.

It suggests that there is a religious reason behind the protest.