This type of classification used to be used when classifying the protostome organisms.
In this type of organism, the oral cavity develops from the blastophore, the initial cavity in the gastrula, an early stage of the development of the embryo.
A is or c is the correct answer
Answer:
Evolution
Explanation:
Evolution is a gradual change in a population that occurs overtime in a species.
The nuclide represented as X is thorium and this is an alpha decay where an alpha particle is removed off.
<h3>What is nuclide?</h3>
A kind of atom or nucleus which is represented by a specific number of protons and neutrons.
The equation given represents an alpha decay. In an alpha decay, an alpha particle is removed off.
The atomic number of the parent nuclide is more than the daughter nuclide by two units and the mass number of the parent is more than that of the daughter nuclide by four units.
Thus, the x is thorium.
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