which of the following keyword search should retrieve the the most results in an online database?

a.beta
b.beta AND blockers
c. beta OR blockers
d. beta NOT blokers

I'd use c for the most results.

But -- if you wanted information on beta blockers, then b. is your best choice.

The keyword search that would retrieve the most results in an online database is option c: beta OR blockers. This search will retrieve all records that contain either the keyword "beta" or the keyword "blockers".

To determine which keyword search should retrieve the most results in an online database, we need to analyze the options provided.

a. "beta": This search will retrieve results that contain the keyword "beta" in an online database.

b. "beta AND blockers": This search will retrieve results that contain both the keywords "beta" and "blockers" in an online database. It narrows down the search to only find results that include both terms.

c. "beta OR blockers": This search will retrieve results that contain either the keyword "beta" or the keyword "blockers" in an online database. It broadens the search to find results that include either term.

d. "beta NOT blockers": This search will retrieve results that contain the keyword "beta" but do not include the keyword "blockers" in an online database. It narrows down the search to exclude results that include the term "blockers".

Out of these options, the one that should retrieve the most results is option c. "beta OR blockers". This is because it includes both the keyword "beta" and the keyword "blockers" but does not exclude any results. It combines the results from both keywords to retrieve the maximum number of possible matches.