What is the broadcast address for the subnet 190.86.168.0/22?

190.86.168.255 is the broadcast for a /24 subnet beginning at 190.86.168.0, not for the larger /22 block.

190.86.255.255 is the broadcast for a /16 subnet (mask 255.255.0.0), which is far larger than the /22 block in question.

A /22 prefix applies a mask of 255.255.252.0, leaving 10 bits for hosts. Starting from 190.86.168.0, the last two bits of the third octet extend the range from 168 through 171, and all eight bits of the fourth octet extend from 0 to 255, placing the highest (broadcast) address at 190.86.171.255.

190.86.169.255 falls within the valid host range of the /22 subnet but is not the highest address, so it cannot be the broadcast address.