F1 Testcross Progeny Phenotype Number
narrow 603
fast, ziązag 609
ZIgzag 209
fast, narrow 201
fast 221
ZIgzag, narrow 237
fast, zigzag, narrow 7
wild type 5

Suppose a geneticist is using a three-point testcross to map three linked Drosophila recessive mutations called f, z, and n, where f is associated with abnormally fast movement; z is associated with zigzag movement pattern; and n is associated with narrow wings. The geneticist first crosses homozygous narrow flies to homozygous fast, zigzag flies. Next, she testcrosses the F1 progeny to fast, zigzag, narrow parents and obtains the following results. Based on these data, select the order of the three genes.

1. seamount a raised footwall block between normal fault creates this 2. syncline break between rocks where a hanging wall rises relative to a footwall 3. hot spring on rolling hills, this a dip between hills 4. volcanic neck created when a block with hanging walls slips down between normal faults 5. caldera underwater volcano that never reaches above sea level 6. horst natural hot water on earth's surface containing many minerals 7. graben underwater volcano whose top is eroded flat by waves 8. crater less than a mile in diameter; looks like a bowl at the top of a volcano 9. guyot magma that filled the central vent that remains after the volcano has eroded 10. reverse fault over 1 mile in diameter; looks like a bowl over a volcano