Fill in the blank with the correct Canadian spelling: Amy's favourite __ is blue.

The correct answer is "colour," which reflects the Canadian spelling that preserves the 'u' in the word. In Canada, the British influence on English means that certain words incorporate additional letters compared to American English. For example, "colour," "flavour," and "neighbour" are all spelled with a 'u' in Canadian English, aligning with British standards.

In contrast, American English simplifies these spellings, using "color," "flavor," and "neighbor" without the 'u.' This distinction is important for recognizing correct spelling in various English dialects. In this case, the context of the sentence emphasizes personal preference and is straightforward, making "colour" the appropriate choice that adheres to regional spelling conventions in Canada. The choice of "favourite" also includes a 'u,' but it is not the word being asked to fill in the blank.