In this task, you are given a question and a context passage. You have to answer the question based on the given passage.

[Q]: What is the area of expertise of scientists who want to measure radiance from vegetation canopies?, Context: Oxygen presents two spectrophotometric absorption bands peaking at the wavelengths 687 and 760 nm. Some remote sensing scientists have proposed using the measurement of the radiance coming from vegetation canopies in those bands to characterize plant health status from a satellite platform. This approach exploits the fact that in those bands it is possible to discriminate the vegetation's reflectance from its fluorescence, which is much weaker. The measurement is technically difficult owing to the low signal-to-noise ratio and the physical structure of vegetation; but it has been proposed as a possible method of monitoring the carbon cycle from satellites on a global scale.
[A]: remote sensing


[Q]: In early August 2008, who was not working for the AFL, Ed Policy or David Baker?, Context: After 12 years as commissioner of the AFL, David Baker retired unexpectedly on July 25, 2008, just two days before ArenaBowl XXII; deputy commissioner Ed Policy was named interim commissioner until Baker's replacement was found. Baker explained, "When I took over as commissioner, I thought it would be for one year. It turned into 12. But now it's time."
[A]: David Baker


[Q]: what group is mentioned fourth?, Context: At various times, there have been cardinals who had only received first tonsure and minor orders but not yet been ordained as deacons or priests. Though clerics, they were inaccurately called "lay cardinals" and were permitted to marry. Teodolfo Mertel was among the last of the lay cardinals. When he died in 1899 he was the last surviving cardinal who was not at least ordained a priest. With the revision of the Code of Canon Law promulgated in 1917 by Pope Benedict XV, only those who are already priests or bishops may be appointed cardinals. Since the time of Pope John XXIII a priest who is appointed a cardinal must be consecrated a bishop, unless he obtains a dispensation.
[A]:
clerics