We know something about family and friends here, but very little about other potential investors, so the answer is E. It might be that 30% was invested by family, 30% by friends, and 40% by some mysterious donor unknown to the person starting the business. Then the family invested the same amount as the friends invested, or $50,000. Or maybe friends invested only 1% of the total, in which case family would have invested 30 times as much, or $1.5 million (the rest of the now $5 million total investment coming from non-family and non-friends).
If there's a trap here, it's that test takers might assume only friends and family invested. But if you assume that's true, then using both statements, friends invested 70% of the total, and family 30%, so family invested 3/7 of what friends invested, and family would then have invested (3/7)(50,000) = 150,000/7 dollars, which is not a possible amount of money (it is an infinite decimal). So that might be a clue that the information is not sufficient even together. Technically the same issue exists in the first example I gave above (the 30% family, 30% friends example) but once you notice there can be other investors, it becomes so clearly E there isn't much reason to come up with perfect scenarios to prove anything.