Question 7

1993 had the biggest increase in nesting sites over the preceding year.

In 1993, the data indicates a significant increase in the number of nesting sites for bluebirds compared to the previous year, demonstrating the effectiveness of the environmental group's initiative.

A) 1992

While 1992 may have shown an increase in nesting sites, it does not surpass the increase observed in 1993. Without specific data indicating a larger increment, this option is not the correct answer.

B) 1990

The year 1990 does not represent a peak in the increase of nesting sites when compared to the succeeding years. The increments noted in later years, especially 1993, overshadow any gains made in 1990.

C) 1993

In 1993, the increase in nesting sites is the highest recorded over the preceding years, reflecting the successful implementation of the nesting boxes that effectively excluded starlings and allowed bluebirds to thrive.

D) 1942

The data regarding 1942 does not show any notable increase in nesting sites compared to the more recent years. The advancements made in the years closer to the present, particularly 1993, indicate that this option is not relevant to the question.

Conclusion

1993 stands out as the year with the most significant increase in bluebird nesting sites due to the exclusion of starlings, as presented in the extract. The other options either reflect lesser increases or are not relevant years for comparison, firmly establishing 1993 as the correct choice based on empirical data.