There are four styles of a notebook available at a store: a plain black one, a glittery silver one, a shiny gold one, and a reflective turquoise one. The store looks at samples of four purchases in a row of these notebooks, with the following results:

{black, gold, gold, silver}

{turquoise, black, silver, gold}

{gold, silver, turquoise, turquoise}

{silver, silver, silver, turquoise}

{silver, black, gold, gold}

{gold, turquoise, black, black}

Using the mean of the sampling distribution of the proportion for each color, which notebook(s) is likely the most popular?

The black notebook.
The gold notebook.
The silver notebook.
The turquoise notebook.
Both the silver and gold notebooks.
Both the black and turquoise notebooks.