Q: Question: "What has been of contention?" Context: "However, the Orthodox claim to absolute fidelity to past tradition has been challenged by scholars who contend that the Judaism of the Middle Ages bore little resemblance to that practiced by today's Orthodox. Rather, the Orthodox community, as a counterreaction to the liberalism of the Haskalah movement, began to embrace far more stringent halachic practices than their predecessors, most notably in matters of Kashrut and Passover dietary laws, where the strictest possible interpretation becomes a religious requirement, even where the Talmud explicitly prefers a more lenient position, and even where a more lenient position was practiced by prior generations." Answer:
A: the Judaism of the Middle Ages bore little resemblance to that practiced by today's Orthodox

Q: Question: "What is thought to be reasoning behind why one might experience emotions?" Context: "Emotions are thought to be related to certain activities in brain areas that direct our attention, motivate our behavior, and determine the significance of what is going on around us. Pioneering work by Broca (1878), Papez (1937), and MacLean (1952) suggested that emotion is related to a group of structures in the center of the brain called the limbic system, which includes the hypothalamus, cingulate cortex, hippocampi, and other structures. More recent research has shown that some of these limbic structures are not as directly related to emotion as others are while some non-limbic structures have been found to be of greater emotional relevance." Answer:
A: behavior

Q: Question: "What type of metals is the second type considered to be?" Context: "Hydrogen is highly soluble in many rare earth and transition metals and is soluble in both nanocrystalline and amorphous metals. Hydrogen solubility in metals is influenced by local distortions or impurities in the crystal lattice. These properties may be useful when hydrogen is purified by passage through hot palladium disks, but the gas's high solubility is a metallurgical problem, contributing to the embrittlement of many metals, complicating the design of pipelines and storage tanks." Answer:
A: Hydrogen is highly soluble in many rare earth and transition metals and is soluble in both nanocrystalline and amorphous metals

Q: Question: "What can be a plants defense?" Context: "Judging relationships based on shared characters requires care, since plants may resemble one another through convergent evolution in which characters have arisen independently. Some euphorbias have leafless, rounded bodies adapted to water conservation similar to those of globular cacti, but characters such as the structure of their flowers make it clear that the two groups are not closely related. The cladistic method takes a systematic approach to characters, distinguishing between those that carry no information about shared evolutionary history such as those evolved separately in different groups (homoplasies) or those left over from ancestors (plesiomorphies) and derived characters, which have been passed down from innovations in a shared ancestor (apomorphies). Only derived characters, such as the spine-producing areoles of cacti, provide evidence for descent from a common ancestor. The results of cladistic analyses are expressed as cladograms: tree-like diagrams showing the pattern of evolutionary branching and descent." Answer:
A:
spine