Summarize the methods by which dna was found to be located in chromosomes.

DNA packaging is the method to convert long DNA into condensed chromosomes. Histone protein is responsible for basic level packaging of DNA into the nucleosome. Histone proteins are positive in nature that neutralize the DNA's negative charge.

A nucleosome consists of eight histone proteins which wraps around 147 bp of DNA. Each nucleosome has linker histone which forms chromatosome.

The next level of organization is the compaction of nucleosome into approx 30nm diameter fiber due to the attraction between nucleosomes.  

Then protein condensin helps in making the 30 nm chromatin fiber to condense more to become a chromosome which is 1000 fold smaller than its original length.

the answer is d (apex) good luck : ))