Refused Tourist Visa Application

[Jalex23]

I applied Canada TRV since my Father will undergo operation by September, I will be the one who will take care of him, and it happened to be on October 10 will be my step brother's wedding in California.

Yes, I travelled to Singapore last January 2017.

This doesn't make sense. You mentioned 3 other family members are Canadian PRs, so they can take care of your father. If they cannot then they can pay for a nurse to help him in those days. Said that your travel to "take care of your dad" is unnecessary and in the worst case attempts to take a job from a Canadian.

You already mentioned you could leave 3 months in a row, so there is little point on adding work ties to your application. It is clear your job is not that important to be considered a tie.

IMO you have no business in Canada and an approval seems unlikely.