The answer should be B. ensuring everyone has signed up
I believe that you forgot to add the figure. However, I'll tell you the difference between the period and the group in the periodic table and you can use these definitions to get the correct answer.
Periods: Each row in the periodic table is called a period (from left to right). Elements of the same period have exactly the same number of atomic orbitals. As you move down the table, each row (period) adds a new atomic orbital. Since the maximum number of orbitals discovered is seven, therefore, you will find that we have seven periods in the periodic table.
Groups: Each vertical column in the periodic table is called a group (from up to down). Elements of the same group have the same number of electrons in the valence shell with the exception of transition elements.
Answer:
The train <u><em>will stop</em></u> at every station.
Explanation:
The use of a correct form of the verb depends on the structure and form of the sentence. Depending on what the sentence is talking about, and how t=it is structured, the verb corresponding to that condition will be used.
In the given sentence, the idea is to use or talk about time in the future, which means, the sentence has to be in the future tense. This means that we will use<u> "will+ verb" </u>to make it into future tense.
Thus, the correct answer will be-
The train <u><em>will stop</em></u> at every station.