Question

select the correct answer from each drop - down menu.
mendeleev’s table of elements was better accepted than those of other scientists at the time because
he went a step further in suggesting that the elements be arranged according to
drop - down menu options: it could accommodate new elements, it could form trends of elements

Explanation:

Mendeleev's periodic table was better because it could accommodate new elements (by leaving gaps for undiscovered elements, which was a key advantage over other arrangements at the time). The first part of the question (about why his table was better) has the correct reasoning related to accommodating new elements, and for the arrangement (the blank after "according to"), Mendeleev arranged elements by atomic mass (though later corrected to atomic number, but in his time, atomic mass was the basis, and the key for the "better accepted" part is the ability to accommodate new elements). Assuming the drop - down for the "better accepted" part has "it could accommodate new elements" as an option (from the visible text snippets like "it could accommodate new elements" in the dropdown), and for the arrangement, the correct basis was atomic mass (but if the dropdown for the arrangement has options, and given the context, the first blank (why his table was better) answer is related to accommodating new elements.

Answer:

For the first part (why Mendeleev’s table was better accepted): it could accommodate new elements.
For the arrangement (elements arranged according to): atomic mass (note: if the dropdown has this option; if the visible dropdown in the image for the arrangement has other options, but based on the context of Mendeleev's work, atomic mass was his basis for arrangement, and later Moseley used atomic number).