With 49.33% in Class 12 Science from UP Board, it may be a bit difficult to get admission in top BCA colleges in Mumbai, as most require 50% or more. However, you can still apply to private colleges or those with management quota. Some colleges may consider your interest and give admission through direct entry. Try colleges like Thakur College, Nirmala College, or Sandesh College. Also, look for online or distance BCA options as a backup.