instruction:
In this task, you will be presented with a context passage, a question about that paragraph, and a possible answer to that question. The task is to check the validity of the answer. Answer with "Yes" or "No".
question:
Fossils can be used to match up rock layers. As organisms change over time, they look different. Older fossils will look different than younger fossils. Some organisms only survived for a short time before going extinct. Knowing what organisms looked like at certain times also helps date rock layers. Some fossils are better than others for this use. The fossils that are very distinct at certain times of Earths history are called index fossils. Index fossils are commonly used to match rock layers. You can see how this works in Figure 2.30. If two rock layers have the same index fossils, then they're probably about the same age. <sep>How are fossils used to match up rock layers?<sep>They match the mineral deposits
answer:
No

question:
Bin Laden reportedly discussed the planes operation with KSM and Atef in a series of meetings in the spring of 1999 at the al Matar complex near Kandahar. KSM's original concept of using one of the hijacked planes to make a media statement was scrapped, but Bin Laden considered the basic idea feasible. Bin Laden, Atef, and KSM developed an initial list of targets. These included the White House, the U.S. Capitol, the Pentagon, and the World Trade Center. According to KSM, Bin Laden wanted to destroy the White House and the Pentagon, KSM wanted to strike the World Trade Center, and all of them wanted to hit the Capitol. No one else was involved in the initial selection of targets. Bin Laden also soon selected four individuals to serve as suicide operatives: Khalid al Mihdhar, Nawaf al Hazmi, Khallad, and Abu Bara al Yemeni. During the al Matar meetings, Bin Laden told KSM that Mihdhar and Hazmi were so eager to participate in an operation against the United States that they had already obtained U.S. visas. KSM states that they had done so on their own after the suicide of their friend Azzam (Nashiri's cousin) in carrying out the Nairobi bombing. KSM had not met them. His only guidance from Bin Laden was that the two should eventually go to the United States for pilot training. Hazmi and Mihdhar were Saudi nationals, born in Mecca. Like the others in this initial group of selectees, they were already experienced mujahideen. They had traveled together to fight in Bosnia in a group that journeyed to the Balkans in 1995. By the time Hazmi and Mihdhar were assigned to the planes operation in early 1999, they had visited Afghanistan on several occasions. Khallad was another veteran mujahid, like much of his family. His father had been expelled from Yemen because of his extremist views. Khallad had grown up in Saudi Arabia, where his father knew Bin Laden, Abdullah Azzam, and Omar Abdel Rahman (the "Blind Sheikh"). <sep>Besides Bin Laden, KSM, and Atef, who else was involved in discussing the initial selection of targets?<sep>Azzam
answer:
No

question:
A stranger in town meets pretty young Susan Martinez De La Cruz and accompanies her to a barbecue , where wealthy Jason Carberry is saying a few words for the recently departed Robin Randall , a citizen who got shot . Jason objects to the stranger's presence , being Susan's guardian and protective of her . He challenges him to a shootout , but the stranger pulls his pistol before Jason's can even clear the holster . Calaveras Kate , a saloon singer who's in love with Jason , is relieved when the stranger declines to pull the trigger . Rafael Moreno suddenly rides into town and picks a fight with the stranger . Their brawl continues until the arrival of Judge Wallace Wintrop and his niece , Sheila , who have come to town from back East and deplore all this random violence out West . The stranger is recognized as Reb Randall , the dead man's brother . He is looking for the killer , who could be Rafael , or could be Jason , or could even be Billy Buckett , the coward of the county . The women hold their breath to see if the men they love will survive . <sep>Who wants to look for the killer?<sep>Robin Randall's brother
answer:
Yes