Disclaimer: you really have to run the modeling for your own situation.
That said, here are the scenarios which are changing constantly. Assuming you are retiring from Merck at 55 and after.
Lump sum - slightly more than $500K.
Life Income option to you alone to age 62 - about 3K a month. After age 62, drops by $50 per month. If you kick the bucket, Merck is free and clear.
Under Life Income with Certain Period & Life Guarantee Options there are three: 5 Year Guarantee Annuity around $2800/month; 10 Year Guarantee Annuity that is about $50 less; then the 15 Year Guarantee Annuity which is another $50 less.
Lastly, the Social Security Option. The Age 62 option (earliest you can retire and receive SS at a reduced amount) is about $4K a month to age 62 and drops down to $2200. The Age 65 option starts at $100 less, then drops to $1800 when you start to receive SS at age 65.
Lump sum or annuities? That you have to figure it out yourself. Risk versus stability. Most of us took a lump sum and roll over to a IRA. You can roll your 401K into it also. The calculation for lump sum is changing constantly and the pot is getting smaller and smaller.
Good luck.