What's your opinion on this?

I think it's been covered up to not cause mass panic. I also think that any of the lifeforms would have died hitting Earth, though.

I think we're also at the stage where we can accept that aliens exist and not go into mass panic.

Where is the option of: UFO's are not real but Aliens are real?

Because i believe in alien life on other planets, but i don't believe in UFO's

I disagree with all of the options. I believe aliens might exist. UFO's I very much believe exist however are they aliens? They could be robots. Honestly if Aliens were among us they would invade us, anyone with the technology to travel to Earth has to have the capabilities to conquer it. What does the US have in Area 51? I have no dang clue but I assume what ever it is it is technologically superior to anything else on earth.

I think theirs a possibility aliens exist , I think theirs a possibility UFO's exist. Then theirs the possibility that the UFO's are aparitions (Spirits) the other possibility is that they are demon's or angels. Their are plenty of possibilities.

I hate to say it but after reading decades of accounts a while back and seeing the testimony of several high ranking government, military, and public figures......I believe.

No. UFOs with an extra terrestrial origin do not exist. I reckon alien lfie exists somewhere in the universe, and even the most conservative estimates applied to the Drake equation suggests that there should be many other advanced races in our galaxy, even though intelligent life would be rare (simply because the numbers we're dealing with are so huge). However, this is something that the human race is still fairly ignorant about. We barely know of any rocky exoplanets, let alone ones that could harbour life. Not to mention the recent findings by Nasa that demonstrate that life does not have to contain the same kinds of chemicals as us, which throws everything off again.

So in short, I reckon life exists elsewhere, but I also think it's unlikely that they've reached us, and to be honest we have no idea what they are or where they might be.

Futurama has told me anything is  possible. So yes.