Time horizon for what?

50/50 is a more appropriate asset allocation five years out from retirement

Depends on how much they have, where their retirement comes from, what a steep drop in this investment would do to their retirement, and how much risk your parents can tolerate.

Do they want to accumulate assets or protect assets?

What percentage is "some" of their savings? If this is 10% mad money then is doesn't matter. If they're investing 90% of their nest egg, 70% stocks is too aggressive.

No one can tell you which portfolio will do better over the next 5 years.

Portfolio A is riskier so if the markets are kind, it'll do better than B. But the tradeoff is a higher likelihood that they could make nothing or even lose a little bit.

If they aren't sure what to do, they can split the difference and go with a 50/50 portfolio which would almost certainly not lose money in a 5-year time frame.

Why is the time horizon 5 years?

If they need this money in 5 years, 100% bonds is the safe option. Generally, in the short term, if not having enough money for something is a concern, that money should be in a savings account, treasuries, or something else that might earn less but won’t lose value.

Portfolio A is ideal for older clients. Keep in mind that in the 5-year timeline, you'll see less returns compared to Portfolio B.